(Lemon gum)
The lemon gum is a tall tree native to Australia with smooth pink, gray or green bark that sheds in spring. Its leaves when crushed emit a delightful lemon scent, popular in potpourris and perfumes, and to freshen the air indoors. Its oil is the major ingredient in some plant-based insect repellents, and a scattering of the leaves crushed or whole repels cockroaches and silver fish around the house. It is a striking specimen plant in semi-tropical zones where it survives outside year round. For a tree, it is extremely fast growing, but can be kept as an annual bedding plant or as a container plant if it is pruned to keep its growth in check. It requires a sunny location.